FORMER Defence Minister Willie O'Dea had no option but to stand down after the Green Party threatened to walk out of government, he revealed yesterday.

Speaking in his home power base of Limerick, Mr O'Dea said it was clear the Greens would no longer support the Government if he remained in office.

"It would have made the continuation of the Government impossible -- that's what I was told," Mr O'Dea said.

He said he been under the "most enormous strain" for the past 10 days, but insisted he bore no animosity to the Green party after he suffered the "ultimate political penalty".

He said he had not made any long-term decision yet as to whether he would continue in politics.

Mr O'Dea said it was in the interests of the country that he had stepped down from the Cabinet.

"It is absolutely in the interests of this country that the Government survives. To protect the stability of the Government, I decided to offer my resignation to the Taoiseach," Mr O'Dea said.

He insisted he was not ordered to go by Taoiseach Brian Cowen, who he credited as being "personally very supportive" to him.

His long-term future in politics now hangs in the balance.

"I have been elected to represent the constituency of Limerick for five years and I have worked very hard to the very best of my ability seven days a week. I am going to continue to represent them, that is my present inclination, but as I say, I haven't even got around to thinking about the future in any serious way yet."

"The one positive is the huge groundswell of support I have got from my constituents, my friends, my canvassers and my supporters," Mr O'Dea continued.

"That has been very, very heartening indeed. Out of every bad, always comes some good, and that has been good."

He said the last week-and-a-half had been "incredibly tough" for him.

"It has been a very, very difficult 10 days for myself and my family. It has been the most enormous strain. Nobody who hasn't gone through this can realise how stressful it has been. It is something I will take to my grave and it is something I certainly wouldn't want to go through again."

He rejected suggestions he had disgraced the office of defence minister.

"I didn't disgrace any office. I made a small mistake. Everyone makes them."

"I paid a very heavy financial penalty for that and I have paid the ultimate political penalty as well.

"I can think of other situations where ministers did far worse and they survived."